Many people wonder if drinking mineral water contributes to kidney stone formation. This article clarifies common misconceptions and provides evidence-based information on mineral water and kidney stone risk.
Understanding Kidney Stones
Kidney stones are hard deposits of minerals and salts that form inside the kidneys. These solid masses vary in size, from a grain of sand to a pea or larger. The most common type is the calcium stone, primarily calcium oxalate, though calcium phosphate stones also occur. Other types include uric acid stones, linked to high-protein diets or fluid loss, and struvite stones, which can develop from urinary tract infections.
Factors increasing kidney stone likelihood include insufficient fluid intake, leading to concentrated urine. Dietary choices like high oxalate or sodium intake can also play a role. Genetic predisposition and medical conditions such as obesity or inflammatory bowel disease are also risk factors.
What is Mineral Water
Mineral water originates from natural underground sources like springs and reservoirs. As it travels, it naturally absorbs dissolved minerals and trace elements, including calcium, magnesium, potassium, sodium, and bicarbonates.
Mineral types and concentrations differ significantly depending on the geological source. The U.S. Food and Drug Administration classifies mineral water as naturally containing at least 250 parts per million (ppm) of total dissolved solids. This mineral content distinguishes it from regular tap or purified water, which may have fewer natural or added minerals.
Mineral Water and Kidney Stone Risk
For most, mineral water minerals do not increase kidney stone risk; they can even offer protective benefits. Adequate fluid intake, whether mineral or tap water, is the most important factor in preventing kidney stones. Diluting urine helps prevent minerals and salts from becoming too concentrated and forming crystals.
Dietary calcium, including from mineral water, is absorbed differently than supplement calcium. When consumed with meals, water’s calcium binds with oxalate in the digestive tract, reducing oxalate absorption into the bloodstream and urine. This binding lowers calcium oxalate stone risk. Studies show that calcium and magnesium-rich mineral water can improve factors for calcium oxalate stone formation by increasing stone inhibitors like magnesium and citrate, and by moderately increasing urine pH.
Water for Kidney Health
Maintaining consistent fluid intake throughout the day is important for kidney health and preventing kidney stones. Guidelines suggest aiming for a daily urine output of at least 2.5 liters, meaning drinking 2.5 to 3 liters of fluids daily. This hydration keeps urine diluted, making it harder for crystal-forming substances to aggregate.
While mineral water is generally beneficial due to its natural mineral content, regular tap or filtered water is also adequate for most people’s hydration needs. The primary goal is consuming enough fluid to produce a good volume of diluted urine. For those with a history of kidney stones, consulting a healthcare provider for advice on fluid intake and diet is recommended.